V. Tretyakov, Natalia, Vladimir A. Fedorov, Evgeniya V. Ketrish, and Oleg M. Permyakov. 2018. “Maintenance of Russian Secondary School students’ Health (organizational and Administrative Aspect)”. International Journal of Engineering & Technology 7 (2.13): 13-17. https://doi.org/10.14419/ijet.v7i2.13.11571.